1.\" Copyright (c) 2002,2003 Alexey Zelkin <phantom@FreeBSD.org> 2.\" All rights reserved. 3.\" Copyright (c) 2024 The FreeBSD Foundation 4.\" 5.\" Portions of this documentation were written by Olivier Certner 6.\" <olce@FreeBSD.org> at Kumacom SARL under sponsorship from the 7.\" FreeBSD Foundation. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd January 5, 2024 31.Dt PTHREAD_ATTR_GET_NP 3 32.Os 33.Sh NAME 34.Nm pthread_attr_get_np 35.Nd get attributes of an existing thread 36.Sh LIBRARY 37.Lb libpthread 38.Sh SYNOPSIS 39.In pthread_np.h 40.Ft int 41.Fn pthread_attr_get_np "pthread_t pid" "pthread_attr_t *dst" 42.Sh DESCRIPTION 43The 44.Fn pthread_attr_get_np 45function is used to retrieve the attributes of the specified thread into an 46existing 47.Vt pthread_attr_t 48structure. 49The attributes' values are the current ones for the target thread, except for 50the stack top address if not properly aligned for the architecture, since in 51this case its value has been adjusted internally before use. 52.Pp 53Argument 54.Fa dst 55must be a pointer to a valid attributes object 56.Po 57it was initialized at some point by 58.Xr pthread_attr_init 3 59and was not destroyed since then 60.Pc . 61After a successful call to 62.Fn pthread_attr_get_np , 63the individual attributes' values can be retrieved as usual via the 64corresponding accessor functions as documented in 65.Xr pthread_attr 3 . 66After a failed call to 67.Fn pthread_attr_get_np , 68the object pointed to by 69.Fa dst 70is left unmodified, and can continue to be used as if the failed call never 71happened. 72.Sh RETURN VALUES 73If successful, 74.Fn pthread_attr_get_np 75function returns 0. 76Otherwise, an error number is returned to indicate the error. 77.Sh EXAMPLES 78This function retrieves the stack size of the thread specified by the 79.Fa pid 80argument: 81.Bd -literal 82size_t 83my_thread_stack_size(pthread_t tid) 84{ 85 pthread_attr_t attr; 86 size_t size; 87 88 pthread_attr_init(&attr); 89 pthread_attr_get_np(tid, &attr); 90 pthread_attr_getstacksize(&attr, &size); 91 pthread_attr_destroy(&attr); 92 return (size); 93} 94.Ed 95.Sh ERRORS 96The 97.Fn pthread_attr_get_np 98function will fail if: 99.Bl -tag -width Er 100.It Bq Er EINVAL 101One of the arguments has an invalid value. 102.It Bq Er ESRCH 103No thread could be found corresponding to that specified by the given 104thread ID. 105.It Bq Er ENOMEM 106There was not enough memory to allocate additional storage needed by the attributes 107object's implementation. 108.El 109.Sh SEE ALSO 110.Xr pthread_attr 3 , 111.Xr pthread_attr_destroy 3 , 112.Xr pthread_attr_getdetachstate 3 , 113.Xr pthread_attr_getinheritsched 3 , 114.Xr pthread_attr_getschedparam 3 , 115.Xr pthread_attr_getschedpolicy 3 , 116.Xr pthread_attr_getscope 3 , 117.Xr pthread_attr_getstack 3 , 118.Xr pthread_attr_getstackaddr 3 , 119.Xr pthread_attr_getstacksize 3 , 120.Xr pthread_attr_init 3 , 121.Xr pthread_np 3 122.Sh AUTHORS 123The 124.Fn pthread_attr_get_np 125function and this manual page were written by 126.An Alexey Zelkin Aq Mt phantom@FreeBSD.org , 127and the latter was revised by 128.An Olivier Certner Aq Mt olce@FreeBSD.org . 129